Chemistry Chapter 2 Measurements and Calculations

The SI base units for time and temperature are

• hour and degree Celsius.
• second and degree Celsius.
• hour and kelvin.
• second and kelvin.

The unit cm³ is used to express 

•  length.
• mass.
• volume. 
• time.

An object’s weight is a measure of

• the force with which it is attracted by gravity.
• the pressure exerted on a scale.
• the amount of material per unit volume.
• the force causing the object to move.

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The SI base unit for mass is the

• gram.
• cubic centimeter. 
• meter. 
• kilogram.

Which of these is not an SI base unit?

• meter
• pound
• kelvin
• ampere

Precision is related to all of these except

• reproducibility of measurements.
• range of measurement values.
• number of significant figures.
• closeness of a measurement to the accepted value.

In division and multiplication, the answer should have the same number of significant figures as the

• number in the calculation with the fewest significant figures.
• number in the calculation with the most significant figures.
• average number of significant figures in the calculation.
• total number of significant figures in the calculation.

The measurement 0.0265 g, rounded off to two significant figures, would be

• 0.026 g. 
• 0.027 g.
• 0.03 g.
• 0.030 g.

The number of significant figures in the measurement 170.040 km

• three. 
• four. 
• five.
• six.

Expressed in scientific notation, 0.0930 m is

• 9.30 × 10⁻⁴ m.
• 9.30 × 10⁻² m. 
• 9.3 × 10⁻³ m.
• 93 × 10⁻³ m.